Tubular pole



Feb- 15, 1955 J. PFlsTERsHAn'ER TUBULAR POLE Filed Nov. 3. 1949 IN V ENTOR.

Josef Pfisirshoer V'I'UBULAR POLE Josef Pfistershamer, Vienna, AustriaApplication November s, 1949, serial No. 125,201

Claims priority, application Austria November 10, 1948 3 Claims. (Cl.189-26) The nvention is concerned with a novel construction of poles,for any carrying and suspen'dng purposes such as for carrying electriclines, street lamps, or the like. More particularly, the nvention isconcerned with tubular poles composed of a number of conical, upwardlytapering tube lengths, telescoped together, said tube lengths consistingof sheets bent and joined together by seams formed' by the length edgesof the sheets. More particularly it is an object of the nvention toutilize to the fullest extent the material of the blanks and to shape itinto the proper form without any waste of material. It is a furtherobject of the nvention to provide closure and secun'ng means at the seamedges of the blanks which make possible the closing of the bent sheetsto form the desired tube lengths or units by simple means and to preventthem etfectively from openrn gA further object of the nvention is astructure of the seams such that the tubular sections or lengths of thepoles are prevented at their telescopic joints from being turned orpivoted relatively to one another, and, furthermore that within thejonts, where the tube lengths or units are telescoped together, theinner ends of the tubular pieces may not bend or fold in and the polethus collapse, as might otherwise occur with thin-walled tubes made ofsheets the edges of which overlap each other at the seams, or the seamsof which are otherwise thickened or re-enforced, or are welded.

It is a further object of 'his nvention to provide a pole of the typedescribed, in which very hard, thin sheets of ferrous or non-ferrousmetal may be used, which sheets, as a rule, can be deformed onlyslightly and cannot be welded at all. The poles of the nvention may,however, be manufactured without the use of any rivets, screws, withoutWelding, or any supplemental `or connecting members or means, andwithout any waste of construction material, from inexpensive hard sheetmaterial which up to now could not be utilized for these purposes.

The nvention is furthermore concerned with novel methods ofmanufacturing such tubular tubes.

In accordance with the nvention, the connection of the sheets bent intotwo half shells or the closure of the seam is etfected by means of oneor more rows of tongues for mutual inter-engagement punched into theedges of the sheets and bent about their roots, off these sheets, thusopening in both overlapping edges slots of equal contour with thetongues, into which opposing slots opposite tongues may mutually beentered. The tongues are pressed off the sheets to an extent whichslightly surpasses the thickness of the sheets, e. g. 1.2 times thisthickness. The tongues of overlapping edges are disposed oppositely ofeach other and are of equal shape. These oppositely arranged tonguespoint in opposite length directions and project from the sheets towardseach other so that the tongues of one half shell are pressed obliquelyoutwards and the tongues of the other half shell obliquely inwards.

The tongues thus formed are then brought into engagement by pushing thetwo half shells laterally over each other so that the co-operating edgesare brought to overlap each other. The tongues of the one of theoverlapping edges are pressed into the slots opened by the bending otfof the tongues of the other edge and conversely, in the manner asexactly fitting safety bolts are inserted into their catehes. When allthe tongues have United States Patent 2,70Z,l03 Patented Feb. 15, 1955penetrated their opposite slots, the tongues are pressed down andcompressed or upset through the application of high pressure. A verystrong, tight and smooth seam is formed in an inexpensive manner withoutany supplemental material and without any waste.

The nvention has for a further object the application of a subsequentlyhardening binding agent between the parts of the seam, between theoverlapping edges and into the interstices between the interlockedtongues and between the tongues and slots, for filling the intersticesor for weatherproofing the seam, or also for further securing theclosure, or several of these purposes.

Advantageously, a soldering means, for brazng or for soft soldering, maybe ntroduced, before the seam is being finally closed, between theoverlapping, seam forming edges with their tongues and slots. Thesesoldering means may be caused to flow while the seam is being compressedby using for instance electric resistance heating, or by heating thetools, or by utilizing the heat of the compressing. Otherwise, the seam,after it had been closed, ever according to the construction materialemployed, may be fixed and simultaneously protected against corrosion,by fire-zincing, spray-coating with melted zinc, rnelted pure aluminumor by other brazng or soft soldermg.

A further object of the nvention is the cutting of the blanks for thehalf shells in pairs from rectangular sheets, by oblique cuts andwithout any waste.

With tubular pieces at which the overlapped length seams are arranged atan angle relatively to the longitudinal axis of the tube length, theblanks of four half shells for two equal conical tube lengths may beobtained, without waste, from two sheets of differing widths by means oftwo oblique cuts dividing the sheets into equal parts, one shell tosupply two equal half shells with the length edges to lie outwards inthe seams, the other sheet to supply two equal half shells with thelength edges to lie inwards in the seams. The connecting tongues of theseams formed by the overlapping edges may be staggered relatively to oneanother in two or more rows and the connecting tongues as well as theslots may be corrugated.

The nvention will now be more fully described with reference to theaccompanying drawings in which an embodiment of the nvention isillustrated by way of example.

In the drawings:

Fig. l is an elevational view of the upper part of a tubular pole withthree tube lengths telescoped together at two jonts, and with a simpleand a double cross arm;

Fig. 2 is a fractional top view of the median or collar part of thedouble cross arm of Fig. 1;

Fig. 3 sla similar view of the collar part of the simple cross arm ofFig. l; v

Fig. 4 is a plan view of an inner half shell of a collar for attaching across arm at the tubular pole, the half shell being shown as extendedinto a plane;

Fig. 5 is a section along line 5-5 of Fig. 4;

Figs. 6 and 7 are plan views of rectangular blanks of dilfering widthwith oblique cuts dividing the blanks into equal parts for equal halfshells, the length edges of the half shells of Fig. 6 to lie outwards inthe seams and those of Fig. 7 inwards;

Fig. 8 is a fractional plan view of a seam closed by overlapping lengthedges;

Fig. 9 is a top view thereof;

Fig. 10 a longtudinal section along line 10-10 of Fig. 8 showing thetongues pressed in the slots however before they had been pressed flat;

Fig. ll is a similar longtudinal section of the seam, the tongues beinginserted into the slots, however before being pressed together; and

Fig. 12 is a top view of the third telescoped joint.

In accordance with the nvention, two equal `blanlrs ar, aa for halfshells a with length edges to lie outwards in the seam and at the tubeto be produced, are Separated from the blank by an oblique cut through anormal rectangular sheet as shown in Fig. 6. These sheets may be of amaterial up to now not employable for the production of tubes, e. g. ofiron sheets of high carbon contents or of extra hard alloyed andtempered aluminum sheets.

avoaios As illustrated in Fig. 7, the blanks bi, b: for two half shells,with the length seams to lie inwards at the finished tubes, are cut in asimilar way by a less inclined cut from a smaller sheet. Any waste ofmaterial is thus avoided.

'Ihe straight blanks ai, az, bi, ba, thus produced are shaped along thewhole of their length edges with tongues or tongue groups z, asillustrated m Figs. 4, 5 and 8 to 11, by means of proper tools,advantageouslyon an eccentric press, or between two wheels provided withkmves. The tongues z are bent about their roots under a proper angle outof the plane of the sheets. After the tongues z and the correspondingslots s, opened by the bending off of the tongues, have been applied tothe blanks, the blanks ai, aa, bi, bs, are pressed into semi-circularorsemi-oval shells a and b, for instance on a rounding otf machine. Inthis bending process the connectmg tongues of the smaller half shells bshould point or be directed outwards and the connecting tongues of thelarger half shells a inwards. Pairs of one half shell a and one halfshell b, each, are so joined together that a conical tubular unit orpole section c, Fig. l, is produced at which both length edges of thehalf shell a from the wider sheet lie to the outside and overlap by thewdth of `the seams the length edges ofthe inner half shell b made fromthe narrower sheet. The connecting tongues z, which in both half shellspoint in opp'osite length drections, will then slide along one another'as'illustrated in Fig. 11. I1 `he tongues, m this displacement forclosing the connection, will thus mutually and positvely guide oneanother into locking position.

When the edges then are pressed together for securing the closure, eachtongue z of the outer half shell, 'as Fig. 10 illustrates in section,will precisely and accurately be guided in the cut or slot of the innersheet edge through its inclined position on the one hand and through thecounter tongue at the inner sheet edge on the other hand and will bepressed, tightly fitting, into position. Concomitantly, each tongue z ofthe inner sheet edge through its inclined position and through thecountertongue of the outer sheet edge will be guided accurately fittinginto the opposite cut of lthe outer sheet edge and pressed into it,tightly fitting, since all the tongues and all the cuts are of equalcontour and are produced by the same tool and are equally spaced apartfrom one another.

Through the punching or cutting process, the tongues z have beenstretched to a slight extent and the edges of the slots have beenslightly countersunk through the penetration of the punch. Owng to thesecharacteristics, the tongues after having fully penetrated the slotsprotrude over the edges of the slots s, and when the pressure applicd issufliciently high will be upset withm the slightly countersunk edges.

An extremely solid and tight seam will thus be produced without anywaste of material or without application of supplemental material andwithout any heat treatment.

The material during this process does not sutfer any reduction of itsstressability or its strength, contrariwise, these characteristics areeven enhanced through the cold deforming process under high pressure.

The conical tube lengths c produced in accordance with the invention areput or telescoped together in the manner of the known conicalconnections, so as to form a tubular pole tapering towards its top. Asillustrated in Fig. 12, at the joint, where the wider end of asubsequent tube piece cs is pushed over the narrower end of thepreceding tube piece cs, in accordance with a development of theinvention, the length edges of the inner half shell of the tube piece czwill adjoin or bear against the length edges of the outer half shell ofthe tube piece ca. The pieces thus may be slid together and circularpoles are fully secured against turning or pivoting of the parts againstone another. The length seams of the individual tube pieces ca, ca, ci,are inclined at a proper angle relatively to the longitudinal axis ofthe pole so that'the adjoining overlapped seams do not overlap oneanother and do not interi'upt the ideal form of the curvature of thecircular or oval cross section. The telescoped tube ends fit closely, onthe whole circumference, without any break in the smooth appearance,which otherwise, in other constructions is unavoidable. The tendency ofthe surface at the end of the inner tube piece in conventionalconnections to bend or fold in, when the pole is subjected to highbending stress, thus is removed and the strength of the whole poleincreased.

Cross arms or pole heads for carrying transmission lines, street lamps,or the like, are provided with sleeves or collars for attaching them atthe pole. These collars correspond as to their form or wdth to the formor wdth of the pole at the place where the arm or head is to be secured,see Figs. 1 to 3. These cross arms t are seated by being telescoped onthe pole from above in the same way and with the same advantages as anytube piece on the other, secure against bending and tuming.

Figs. l and 2 illustrate a cross arm ta for two transmission lnes. Atthe cross arm, which consists of two parts, there are secured the twohalf shells hi and hz in such a manner that these half shells connectthe cross arm parts and with them together form a conical collar orsleeve embracing the pole, the length edges of the seams of the halfshell h: bearing against the outer edges of the length seams of the tubepiece ci.

Fig. 3 illustrates a simple cross arm which is mounted about the pole,at m, in such a manner that it itself forms the one half of the collar.The inner half shell h: closes the collar and bears with its lengthedges against the outer edges of the length seams of tube piece ci, thuspreventing any tuming or pivoting of` the cross arm. The

connecting seams of the collars and of the cross arms all areadvantageously executed in accordance with the invention, in the samemanner as the seams connecting and closing the half shells of theindividual tube pieces of the pole.

Figs. 4 and 5 show the inner half of a collar, extended into a plane,for securing the cross arms to the pole. All the connecting tongues z ofthe collars or their halves, which are to he connected with the crossarms, are directed outwards and all the connecting tongues of the crossarms are directed inwards.

The overlapped seams with their connecting tongues and slots may becoated, before the seam is being closed, with a subsequently hardeningbindingimeans or agent which, when solidified or hardened, will opposethe opening of the seams and may also protect the parts thus coatedagainst adverse effects of the weather. The binding means may also be inthe form of a strip or wire to be inserted into the seam. The bindingmeans may further be a solder which, during the compression of the seam,may be melted through electric resistance heating in the manner ofresistance welding, or by otherwise heating the tools, or by utilizingthe heat of the pressure applied to the seam.

The overlapping edges which had been closed and form the seam, everaccording to the material employed, may be fixed and protected' againstcorrosion by fire-zincing, spraying of melted zinc, melted aluminum orother brazing or soft soldering.

I claim:

1. In a pole structure composed of a number of upwardly tapering tubularpole Sections, each pole section having an upwardly taperingfrusto-conical shape and consisting of circularly curved metal sheetseach having a longitudinal marginal portion overlapping the longitudinalmarginal portion of the adjacent sheet, each of said two overlappingportions having a longitudinally aligned row of cut-out tonguesprojecting angularly away from the sheet surface and forming adjacent toeach tongue an opening of the same contour as said tongue, the openingsin each row being alternately above and below the tongues and thetongues having a height substantially equal to the thickness of saidsheet, the tongues of each marginal portion being compressed in thedirection of their height and engagement with the respective openings ofthe other portion and forrning a rigid lap seam together thercwith.

2. A cross-armed pole structure, comprsing a tubular member having anupwardly tapering frusto-conical shape and having longitudinal lapseams, a horizontal hollow cross arm comprising two half-shell shapedparts, said two parts forming together a frusto-conical collar embracingsaid tubular member and ioining said arm with said member, said twoparts having two respective vertical marginal portions overlapping eachother, each of said two overlapping portions having a longitudinallyaligned row of cut-out tongues projecting angularly away from themarginal portion and forming adjacent to each tongue an opening of thesame contour as said tongue, the openings in each row being altematelyto one and the other side of the tongues and the tongues having a heightsubstantially equal to the thickness of said parts, the tongues of eachmarginal portion being compressed in the direction of their height andin fastening engagement with 5 t the respective openn s of the otherportion and formng a rigld lap seam toge er therewith.

3. A tubular pole structure, comprising a sheet structure of metal, saidsheet structure having two longitudinal marginal rtions overlapping eachother, each of said two overlappmg portions having a longitudinallyaligned row of cut-out tongues proiectrng angularly away from the sheetsurface and forming adjacent to each tongue an opening of the samecontour as said tongue, the openings in each row being alternately aboveand below the tongues and the tongues having a height substantiallyequal to the sheet thckness, the tongues of each margnal portion beingin tight engagement with the respective openings of the other portionand formng a rigd lap seam together therewith.

6 Refermcescltedinthelileofthspatent UNITED STATES PATENTS

